#include "Test.h"
#include <fstream>
#include <cstdio>
#include <string>
#include "Buffer.h"

static std::string read_all(const std::string &path) {
    std::ifstream in(path, std::ios::binary);
    return std::string((std::istreambuf_iterator<char>(in)), std::istreambuf_iterator<char>());
}

TEST(Buffer_SaveAs_and_Save_new_file) {
    const std::string path = "./.kte_ut_buffer_io_1.tmp";
    std::remove(path.c_str());

    Buffer b;
    // insert two lines
    b.insert_text(0, 0, std::string("Hello, world!\n"));
    b.insert_text(1, 0, std::string("Second line\n"));

    std::string err;
    ASSERT_TRUE(b.SaveAs(path, err));
    ASSERT_EQ(err.empty(), true);

    // append another line then Save()
    b.insert_text(2, 0, std::string("Third\n"));
    b.SetDirty(true);
    ASSERT_TRUE(b.Save(err));
    ASSERT_EQ(err.empty(), true);

    std::string got = read_all(path);
    ASSERT_EQ(got, std::string("Hello, world!\nSecond line\nThird\n"));

    std::remove(path.c_str());
}

TEST(Buffer_Save_after_Open_existing) {
    const std::string path = "./.kte_ut_buffer_io_2.tmp";
    std::remove(path.c_str());
    {
        std::ofstream out(path, std::ios::binary);
        out << "abc\n123\n";
    }

    Buffer b;
    std::string err;
    ASSERT_TRUE(b.OpenFromFile(path, err));
    ASSERT_EQ(err.empty(), true);

    b.insert_text(2, 0, std::string("tail\n"));
    b.SetDirty(true);
    ASSERT_TRUE(b.Save(err));
    ASSERT_EQ(err.empty(), true);

    std::string got = read_all(path);
    ASSERT_EQ(got, std::string("abc\n123\ntail\n"));
    std::remove(path.c_str());
}

TEST(Buffer_Open_nonexistent_then_SaveAs) {
    const std::string path = "./.kte_ut_buffer_io_3.tmp";
    std::remove(path.c_str());

    Buffer b;
    std::string err;
    ASSERT_TRUE(b.OpenFromFile(path, err));
    ASSERT_EQ(err.empty(), true);
    ASSERT_EQ(b.IsFileBacked(), false);

    b.insert_text(0, 0, std::string("hello, world"));
    b.insert_text(0, 12, std::string("\n"));
    b.SetDirty(true);
    ASSERT_TRUE(b.SaveAs(path, err));
    ASSERT_EQ(err.empty(), true);

    std::string got = read_all(path);
    ASSERT_EQ(got, std::string("hello, world\n"));
    std::remove(path.c_str());
}